Platelet glycoprotein IIIa (platelet antigen 1/platelet antigen 2) polymorphism and 1-year outcome in patients with stable coronary artery disease.

Platelet glycoprotein IIb/IIIa is a membrane receptor which plays a key role in coronary artery disease and thrombotic events. However, there is a considerable controversy regarding the clinical impact of glycoprotein IIIa platelet antigen 1 (PIA1)/platelet antigen 2 (PIA2) polymorphism as a risk factor for myocardial infarction. To evaluate the association between glycoprotein IIIa PIA1/PIA2 polymorphism and 1-year cardiovascular events occurrence in aspirin-treated patients with stable coronary artery disease. We prospectively included 188 postacute coronary syndrome patients (183 men) aged 59 ± 10 years and receiving aspirin (250 mg/day). The clinical outcome at 1 year was the composite end point of nonfatal myocardial infarction, stroke, recurrent unstable angina or cardiac death. Genotyping for PIA1/PIA2 polymorphism was conducted using PCR and restriction fragment length polymorphism analysis. The genotype distribution of glycoprotein IIIa PIA1/PIA2 polymorphism was PIA1/PIA1, 55.3%; PIA1/PIA2, 39.3% and PIA2/PIA2, 4%. Incidence of composite end point in homozygous PIA1/PIA1 carriers was significantly higher than in PIA2/PIA2 and PIA1/PIA2 patients [14.4 vs. 3.6% odds ratio 4.5 (1.2-16.6, 95% confidence interval); P=0.0121. Multivariate analysis identified three strong predictive factors of cardiac death: age more than 65 years [odds ratio = 6.8, (1.4-34, 95% confidence interval); P= 0.0181, ventricular ejection fraction less than 50% [odds ratio = 8.6, (1.7-42.6, 95% confidence interval); P= 0.008] and homozygous PIA1/PIA1 genotype [odds ratio = 8.8, (1.0-78.6, 95% confidence interval); P=0.014]. Our results demonstrated that glycoprotein IIIa PIA1/PIA1 genotype carriers have a significantly increased risks of acute vascular ischemic events associated with a poor prognosis at 1 year. These postacute coronary syndrome patients might require an optimized secondary antithrombotic prophylaxis strategy.